{"id":"F2006B05547","name":"AD/PA-25/1 - Fin Post - Modification","slug":"ad-pa-25-1-fin-post-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46489,"registerId":"commonwealth-F2006B05547-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-25/1 - Fin Post - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Piper PA-25 (Pawnee) Series Aeroplanes\n\n \n\nAD/PA-25/1 Fin Post - Modification 8/60\n\nApplicability: Model PA-25 with S/Nos. 25-3 to 25-123, 25-125 to 25-203, 25-206 to 25-268, 25-\n\n273 to 25-355.\n\n \n\nDocument: Piper SL 335. Compliance: Before 1 September 1971.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2470},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow, technical scope issued in 1960: mandating a specific structural modification to address a fin post defect in early Piper PA-25 aircraft. It has not expanded beyond this discrete airworthiness issue."},"complexity_factors":["Extremely brief text (approximately 50 words of substantive content)","Single unconditional compliance requirement with no exceptions, exemptions, or alternative methods","Full technical details incorporated by external reference to manufacturer document (Piper SL 335) rather than included in the text","Applicability determined solely by aircraft serial number ranges with no conditional logic"],"plain_english_summary":"This Airworthiness Directive from CASA legally requires owners of specified early-model Piper PA-25 \"Pawnee\" aircraft (serials ~25-3 to 25-355, with exceptions) to perform a structural modification to the fin post per Piper Service Letter 335. The modification addressed a tail-attachment defect and carried a compliance deadline of 1 September 1971. It’s mandatory because the issue affects structural integrity and flight safety."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-25-1-fin-post-modification","history":"/api/acts/ad-pa-25-1-fin-post-modification/history","analysis":"/api/acts/ad-pa-25-1-fin-post-modification/analysis","conflicts":"/api/acts/ad-pa-25-1-fin-post-modification/conflicts","importantCases":"/api/acts/ad-pa-25-1-fin-post-modification/important-cases","documents":"/api/acts/ad-pa-25-1-fin-post-modification/documents"}}